@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

/* =============================================
   Theme System — CSS Custom Properties
   ============================================= */
:root {
  /* Theme: Industrial Orange (default) */
  --primary: #ff8c00;
  --primary-dark: #e07b00;
  --primary-light: #ffa94d;
  --primary-rgb: 255, 140, 0;
  --primary-bg: rgba(var(--primary-rgb), 0.1);

  --dark: #1a252f;
  --dark-medium: #2c3e50;
  --gray-bg: #f8f9fa;
  --gray-border: #e9ecef;
  --text: #2d3436;
  --text-muted: #636e72;
  --footer-bg: #1a252f;
  --footer-text: rgba(255,255,255,0.7);

  --card-bg: #fff;
  --body-bg: #fff;
  --header-bg: rgba(255,255,255,0.95);
  --hero-bg: linear-gradient(135deg, #1a252f 0%, #2c3e50 100%);
  --hero-text: #fff;
  --hero-text-muted: rgba(255,255,255,0.7);
  --hero-glow: rgba(var(--primary-rgb), 0.15);
  --section-alt-bg: #f8f9fa;
  --badge-bg: rgba(var(--primary-rgb), 0.1);
  --border-light: rgba(0,0,0,0.04);

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);

  --radius: 10px;
  --radius-sm: 6px;
  --radius-lg: 16px;
}

/* Theme: Professional Blue */
[data-theme="blue"] {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #60a5fa;
  --primary-rgb: 37, 99, 235;
  --dark: #0f172a;
  --dark-medium: #1e293b;
  --footer-bg: #0f172a;
  --hero-bg: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
}

/* Theme: Modern Gray */
[data-theme="slate"] {
  --primary: #e17055;
  --primary-dark: #c75b45;
  --primary-light: #f0987a;
  --primary-rgb: 225, 112, 85;
  --dark: #1a1a2e;
  --dark-medium: #2d2d44;
  --gray-bg: #f1f0f5;
  --footer-bg: #1a1a2e;
  --hero-bg: linear-gradient(135deg, #1a1a2e 0%, #2d2d44 100%);
}

/* Theme: Clean White */
[data-theme="white"] {
  --primary: #2ecc71;
  --primary-dark: #27ae60;
  --primary-light: #6ee7a0;
  --primary-rgb: 46, 204, 113;
  --dark: #1a2639;
  --dark-medium: #2c3e50;
  --gray-bg: #f0f4f8;
  --gray-border: #dce4ed;
  --text: #334155;
  --text-muted: #6b7b8d;
  --card-bg: #fff;
  --body-bg: #f8fafc;
  --header-bg: rgba(255,255,255,0.92);
  --footer-bg: #1a2639;
  --hero-bg: linear-gradient(135deg, #1a2639 0%, #2c3e50 100%);
  --section-alt-bg: #f0f4f8;
}

/* Theme: Tech Blue-Red (inspired by 義展機械) */
[data-theme="tech"] {
  --primary: #1a73e8;
  --primary-dark: #1557b0;
  --primary-light: #4a9af5;
  --primary-rgb: 26, 115, 232;
  --primary-bg: rgba(var(--primary-rgb), 0.08);
  --dark: #0d1b2a;
  --dark-medium: #1b2838;
  --gray-bg: #eef2f7;
  --gray-border: #dce3ed;
  --text: #1a2332;
  --text-muted: #5a6c7e;
  --card-bg: #fff;
  --body-bg: #f7f9fc;
  --header-bg: rgba(13, 27, 42, 0.97);
  --footer-bg: #0d1b2a;
  --hero-bg: linear-gradient(135deg, #0d1b2a 0%, #1b2838 100%);
  --section-alt-bg: #eef2f7;
  --hero-glow: rgba(var(--primary-rgb), 0.12);
  --badge-bg: rgba(var(--primary-rgb), 0.1);
  --border-light: rgba(255,255,255,0.06);
}
[data-theme="tech"] .hero h1,
[data-theme="tech"] .hero p { text-shadow: 0 2px 20px rgba(0,0,0,0.3); }
[data-theme="tech"] .menu a { color: rgba(255,255,255,0.8); }
[data-theme="tech"] .menu a:hover { background: rgba(255,255,255,0.08); color: #fff; }
[data-theme="tech"] .menu a.active { background: var(--primary); color: #fff; }
[data-theme="tech"] .header .logo span { color: #fff; }
[data-theme="tech"] .hamburger span { background: #fff; }
[data-theme="tech"] .btn-outline { border-color: var(--primary); color: var(--primary); }
[data-theme="tech"] .btn-outline:hover { background: var(--primary); color: #fff; }

/* Theme: Industrial Bold (inspired by Caterpillar) */
[data-theme="bold"] {
  --primary: #f5a623;
  --primary-dark: #d4891a;
  --primary-light: #f8c557;
  --primary-rgb: 245, 166, 35;
  --primary-bg: rgba(var(--primary-rgb), 0.12);
  --dark: #0d0d0d;
  --dark-medium: #1a1a1a;
  --gray-bg: #1a1a1a;
  --gray-border: #2a2a2a;
  --text: #e8e8e8;
  --text-muted: #9a9a9a;
  --card-bg: #1a1a1a;
  --body-bg: #0d0d0d;
  --header-bg: rgba(0,0,0,0.95);
  --header-text: #fff;
  --footer-bg: #000;
  --hero-bg: linear-gradient(135deg, #0d0d0d 0%, #1a1a1a 100%);
  --section-alt-bg: #111;
  --hero-glow: rgba(var(--primary-rgb), 0.1);
  --badge-bg: rgba(var(--primary-rgb), 0.15);
  --border-light: rgba(255,255,255,0.06);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.5);
}
[data-theme="bold"] .section-title { color: #fff; }
[data-theme="bold"] h1, [data-theme="bold"] h2, [data-theme="bold"] h3, [data-theme="bold"] h4 { color: #fff; }
[data-theme="bold"] .card-title { color: #fff; }
[data-theme="bold"] .card-text { color: var(--text-muted); }
[data-theme="bold"] .menu a { color: rgba(255,255,255,0.8); }
[data-theme="bold"] .menu a:hover { background: rgba(255,255,255,0.06); color: var(--primary); }
[data-theme="bold"] .menu a.active { background: var(--primary); color: #000; font-weight: 700; }
[data-theme="bold"] .header .logo span { color: #fff; }
[data-theme="bold"] .hamburger span { background: #fff; }
[data-theme="bold"] .btn-outline { border-color: var(--primary); color: var(--primary); }
[data-theme="bold"] .btn-outline:hover { background: var(--primary); color: #000; }
[data-theme="bold"] .pagination a { border-color: #333; color: var(--text-muted); }
[data-theme="bold"] .pagination a:hover { border-color: var(--primary); color: var(--primary); }
[data-theme="bold"] .pagination .current { background: var(--primary); color: #000; border-color: var(--primary); }

/* Theme: Corporate Clean (inspired by DOW / DuPont) */
[data-theme="corporate"] {
  --primary: #0056b3;
  --primary-dark: #003d82;
  --primary-light: #4a8fd4;
  --primary-rgb: 0, 86, 179;
  --primary-bg: rgba(var(--primary-rgb), 0.06);
  --dark: #1a2634;
  --dark-medium: #2c3e50;
  --gray-bg: #f4f6f9;
  --gray-border: #dfe5ed;
  --text: #1e2a3a;
  --text-muted: #6b7a8f;
  --card-bg: #fff;
  --body-bg: #fafbfc;
  --header-bg: rgba(255,255,255,0.92);
  --footer-bg: #1a2634;
  --hero-bg: linear-gradient(135deg, #1a2634 0%, #2c3e50 100%);
  --section-alt-bg: #f4f6f9;
  --hero-glow: rgba(var(--primary-rgb), 0.1);
  --badge-bg: rgba(var(--primary-rgb), 0.06);
  --border-light: rgba(0,0,0,0.04);
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 3px 10px rgba(0,0,0,0.05);
  --shadow-lg: 0 6px 24px rgba(0,0,0,0.08);
}
[data-theme="corporate"] .section-title { letter-spacing: 1px; }
[data-theme="corporate"] .section-title::after { width: 40px; height: 2px; }
[data-theme="corporate"] .card { border: 1px solid var(--gray-border); }
[data-theme="corporate"] .card:hover { border-color: var(--primary); }

/* Layout: Boxed */
body.boxed-layout .container {
  max-width: 1100px;
  border-radius: var(--radius-lg);
}
body.boxed-layout .section,
body.boxed-layout .hero,
body.boxed-layout .cta-section,
body.boxed-layout .footer {
  padding-left: 20px;
  padding-right: 20px;
}
body.boxed-layout .header .nav {
  max-width: 1100px;
  margin: auto;
  padding: 0 20px;
}

/* === Reset & Base === */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', 'Segoe UI', Arial, sans-serif;
  margin: 0; padding: 0;
  color: var(--text); line-height: 1.7;
  background: var(--body-bg);
  -webkit-font-smoothing: antialiased;
  transition: background 0.4s, color 0.4s;
}
a { color: var(--primary); transition: all 0.3s; text-decoration: none; }
a:hover { color: var(--primary-dark); }
img { max-width: 100%; height: auto; display: block; }
.container { width: 90%; max-width: var(--container-width, 1200px); margin: auto; }

/* === Typography === */
h1, h2, h3, h4 { font-weight: 700; line-height: 1.3; color: var(--dark-medium); }
.section-title {
  text-align: center; font-size: 30px; font-weight: 800;
  margin-bottom: 50px; color: var(--dark-medium); letter-spacing: -0.5px;
  position: relative; padding-bottom: 15px;
}
.section-title::after {
  content: ''; position: absolute; bottom: 0; left: 50%;
  transform: translateX(-50%);
  width: 60px; height: 3px; background: var(--primary); border-radius: 2px;
}

/* === Header / Navigation === */
.header {
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 1px 3px rgba(0,0,0,0.06);
  padding: 0;
  position: sticky; top: 0; z-index: 100;
  border-bottom: 1px solid var(--border-light);
  transition: all 0.3s;
}
.header .nav {
  display: flex; justify-content: space-between;
  align-items: center; height: 64px;
  transition: height 0.3s;
}
.header.scrolled .nav { height: 52px; }
.header .logo {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none;
}
.header .logo img { height: 36px; width: auto; transition: height 0.3s; }
.header.scrolled .logo img { height: 28px; }
.header .logo span {
  font-size: 18px; font-weight: 700; color: var(--dark-medium);
  letter-spacing: -0.3px; transition: font-size 0.3s;
}
.header.scrolled .logo span { font-size: 16px; }
.header .logo span .highlight { color: var(--primary); }
.menu { list-style: none; display: flex; margin: 0; padding: 0; gap: 4px; }
.menu li { margin: 0; }
.menu a {
  text-decoration: none; color: var(--dark-medium);
  font-weight: 500; font-size: 14px; padding: 8px 16px;
  border-radius: var(--radius-sm); transition: all 0.25s;
  position: relative;
}
.menu a:hover { background: var(--primary-bg); color: var(--primary); }
.menu a.active {
  background: var(--primary); color: #fff; font-weight: 600;
}

/* === Hamburger Menu === */
.hamburger { display: none; cursor: pointer; background: none; border: none; padding: 8px; }
.hamburger span {
  display: block; width: 24px; height: 2.5px;
  background: var(--dark-medium); margin: 5px 0;
  transition: all 0.3s; border-radius: 2px;
}

/* === Hero Section === */
.hero {
  position: relative;
  background: var(--hero-bg);
  color: var(--hero-text); text-align: center; padding: 64px 20px;
  overflow: hidden;
}
.hero::before {
  content: ''; position: absolute; top: 0; left: 0;
  width: 100%; height: 100%;
  background: radial-gradient(ellipse at 30% 50%, var(--hero-glow) 0%, transparent 60%);
  pointer-events: none;
}
.hero h1 { font-size: 40px; font-weight: 800; margin: 0 0 10px; color: var(--hero-text); letter-spacing: -0.5px; }
.hero p { font-size: 17px; color: var(--hero-text-muted); margin: 0; max-width: 600px; margin-left: auto; margin-right: auto; }
.hero .hero-accent { color: var(--primary); }

/* === Banner Carousel === */
.banner-carousel {
  position: relative; width: 100%; overflow: hidden;
  background: var(--dark);
}
.carousel-track {
  position: relative; width: 100%;
  aspect-ratio: 16 / 5; max-height: 600px; min-height: 250px;
}
.carousel-slide {
  position: absolute; top: 0; left: 0;
  width: 100%; height: 100%;
  opacity: 0; transition: opacity 0.8s ease-in-out;
}
.carousel-slide.active { opacity: 1; }
.carousel-slide img { width: 100%; height: 100%; object-fit: cover; display: block; }
.carousel-caption {
  position: absolute; bottom: 40px; left: 50%;
  transform: translateX(-50%);
  background: rgba(0,0,0,0.55);
  color: #fff; padding: 10px 30px;
  border-radius: var(--radius-sm); font-size: 18px; font-weight: 500;
  white-space: nowrap; backdrop-filter: blur(4px);
}
.carousel-btn {
  position: absolute; top: 50%; transform: translateY(-50%);
  background: rgba(0,0,0,0.35); color: #fff; border: none;
  padding: 14px 18px; font-size: 20px;
  cursor: pointer; border-radius: var(--radius-sm);
  transition: all 0.3s; z-index: 10;
  backdrop-filter: blur(4px);
}
.carousel-btn:hover { background: var(--primary); }
.carousel-btn.prev { left: 16px; }
.carousel-btn.next { right: 16px; }
.carousel-dots {
  position: absolute; bottom: 15px;
  left: 50%; transform: translateX(-50%);
  display: flex; gap: 8px; z-index: 10;
}
.dot {
  width: 12px; height: 12px; border-radius: 50%;
  background: rgba(255,255,255,0.45);
  cursor: pointer; transition: all 0.3s;
}
.dot.active { background: var(--primary); transform: scale(1.2); }

/* === About Page: Stats Counter === */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px; margin: 48px 0;
}
.stat-item {
  text-align: center; padding: 32px 16px;
  background: var(--card-bg); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); border: 1px solid var(--gray-border);
}
.stat-item .stat-number {
  font-size: 42px; font-weight: 800; color: var(--primary);
  line-height: 1.2;
}
.stat-item .stat-label {
  font-size: 14px; color: var(--text-muted); margin-top: 8px;
  font-weight: 500;
}

/* === Product Filter Tabs === */
.filter-tabs {
  display: flex; flex-wrap: wrap; gap: 8px;
  justify-content: center; margin-bottom: 36px;
}
.filter-tab {
  padding: 8px 20px; border-radius: 25px; border: 1px solid var(--gray-border);
  background: var(--card-bg); color: var(--text-muted); font-size: 14px;
  font-weight: 500; cursor: pointer; transition: all 0.25s;
  font-family: 'Inter', sans-serif;
}
.filter-tab:hover { border-color: var(--primary); color: var(--primary); }
.filter-tab.active {
  background: var(--primary); color: #fff; border-color: var(--primary);
}

/* === Sections === */
.section { padding: 64px 0; }
.section-alt { background: var(--section-alt-bg); }

/* === Grid === */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 28px;
}

/* === Cards === */
.card {
  background: var(--card-bg); border: none; border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow-sm);
  transition: all 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}
.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}
.card img { width: 100%; height: 220px; object-fit: cover; }
.card-body { padding: 22px; }
.card-title { font-size: 17px; font-weight: 600; margin: 0 0 8px; color: var(--dark-medium); }
.card-text { color: var(--text-muted); font-size: 14px; line-height: 1.6; margin: 0 0 16px; }
.card-meta {
  font-size: 13px; color: var(--text-muted); margin-bottom: 10px;
  display: flex; align-items: center; gap: 6px;
}
.card-link {
  color: var(--primary); font-weight: 600; font-size: 14px;
  display: inline-flex; align-items: center; gap: 4px;
}
.card-link:hover { gap: 8px; }

/* === Product category badge === */
.category-badge {
  display: inline-block; padding: 3px 10px; font-size: 11px; font-weight: 600;
  background: var(--badge-bg); color: var(--primary);
  border-radius: 20px; margin-bottom: 10px; letter-spacing: 0.3px;
}

/* === Sidebar (Products page) === */
.sidebar-card {
  background: var(--card-bg); padding: 24px; border-radius: var(--radius);
  box-shadow: var(--shadow-sm); border: 1px solid var(--gray-border);
}
.sidebar-card h3 {
  font-size: 15px; font-weight: 700; text-transform: uppercase;
  letter-spacing: 1px; margin: 0 0 16px; padding-bottom: 12px;
  border-bottom: 2px solid var(--primary); color: var(--dark-medium);
}
.sidebar-card ul { list-style: none; padding: 0; margin: 0; }
.sidebar-card li { margin-bottom: 6px; }
.sidebar-card li a {
  display: block; padding: 7px 12px; border-radius: var(--radius-sm);
  color: var(--dark-medium); font-size: 14px; font-weight: 500;
  transition: all 0.2s;
}
.sidebar-card li a:hover { background: var(--primary-bg); color: var(--primary); }
.sidebar-card li a.active { background: var(--primary-bg); color: var(--primary); font-weight: 600; }

/* === Photo Gallery === */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px; margin-top: 20px;
}
.gallery-grid .gallery-item {
  position: relative; border-radius: var(--radius-sm);
  overflow: hidden; cursor: pointer; aspect-ratio: 4 / 3;
}
.gallery-grid .gallery-item img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 0.4s; display: block;
}
.gallery-grid .gallery-item:hover img { transform: scale(1.06); }
.gallery-grid .gallery-item .gallery-caption {
  position: absolute; bottom: 0; left: 0; right: 0;
  background: linear-gradient(transparent, rgba(0,0,0,0.7));
  color: #fff; padding: 20px 10px 8px; font-size: 13px;
  opacity: 0; transition: opacity 0.3s;
}
.gallery-grid .gallery-item:hover .gallery-caption { opacity: 1; }

/* === Lightbox === */
.lightbox-overlay {
  display: none; position: fixed; top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0,0,0,0.92); z-index: 9999;
  justify-content: center; align-items: center; flex-direction: column;
}
.lightbox-overlay.active { display: flex; }
.lightbox-overlay img {
  max-width: 90%; max-height: 80vh;
  border-radius: var(--radius); box-shadow: 0 0 40px rgba(0,0,0,0.5);
  object-fit: contain;
}
.lightbox-overlay .lb-caption {
  color: #ccc; margin-top: 12px; font-size: 14px; text-align: center; max-width: 80%;
}
.lightbox-overlay .lb-close {
  position: absolute; top: 20px; right: 30px;
  background: none; border: none; color: #fff;
  font-size: 40px; cursor: pointer; line-height: 1; transition: color 0.3s;
}
.lightbox-overlay .lb-close:hover { color: var(--primary); }
.lightbox-overlay .lb-nav {
  position: absolute; top: 50%; transform: translateY(-50%);
  background: rgba(255,255,255,0.12); color: #fff; border: none;
  padding: 20px 16px; font-size: 28px; cursor: pointer;
  border-radius: var(--radius-sm); transition: all 0.3s;
}
.lightbox-overlay .lb-nav:hover { background: rgba(var(--primary-rgb), 0.7); }
.lightbox-overlay .lb-prev { left: 20px; }
.lightbox-overlay .lb-next { right: 20px; }
.lightbox-overlay .lb-counter {
  position: absolute; bottom: 20px; color: rgba(255,255,255,0.5); font-size: 14px;
}

/* === YouTube Embed === */
.video-container {
  position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden;
  border-radius: var(--radius-sm); margin: 20px 0; background: #000;
}
.video-container iframe {
  position: absolute; top: 0; left: 0;
  width: 100%; height: 100%; border: none;
}

/* === Buttons === */
.btn-orange {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 11px 28px; background: var(--primary); color: #fff;
  text-decoration: none; border-radius: var(--radius-sm); font-weight: 600;
  font-size: 14px; transition: all 0.3s; border: none; cursor: pointer;
}
.btn-orange:hover { background: var(--primary-dark); color: #fff; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(var(--primary-rgb), 0.35); }
.btn-outline {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 11px 28px; border: 2px solid var(--dark-medium); color: var(--dark-medium);
  text-decoration: none; border-radius: var(--radius-sm); font-weight: 600;
  font-size: 14px; transition: all 0.3s;
}
.btn-outline:hover { background: var(--dark-medium); color: #fff; }

/* === Footer === */
.footer {
  background: var(--footer-bg); color: var(--footer-text);
  padding: 60px 0 0; margin-top: 60px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1.5fr;
  gap: 48px;
}
.footer h4 {
  color: #fff; font-size: 15px; font-weight: 700; text-transform: uppercase;
  letter-spacing: 1px; margin: 0 0 20px;
}
.footer p { font-size: 14px; line-height: 1.7; margin: 0 0 10px; }
.footer a { color: rgba(255,255,255,0.6); }
.footer a:hover { color: var(--primary); }
.footer ul { list-style: none; padding: 0; margin: 0; }
.footer ul li { margin-bottom: 8px; }
.footer ul li a { font-size: 14px; display: inline-flex; align-items: center; gap: 8px; }
.footer .footer-brand { font-size: 22px; font-weight: 800; color: #fff; margin-bottom: 12px; }
.footer .footer-brand .highlight { color: var(--primary); }
.footer .contact-item { display: flex; align-items: flex-start; gap: 10px; margin-bottom: 12px; font-size: 14px; }
.footer .contact-item i { color: var(--primary); margin-top: 4px; min-width: 16px; }
.footer-bottom {
  margin-top: 48px; padding: 20px 0; text-align: center;
  border-top: 1px solid rgba(255,255,255,0.08);
  font-size: 13px; color: rgba(255,255,255,0.4);
}

/* === CTA Section (homepage) === */
.cta-section {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: #fff; text-align: center; padding: 60px 20px;
}
.cta-section h2 { color: #fff; font-size: 32px; font-weight: 800; margin: 0 0 10px; }
.cta-section p { font-size: 16px; opacity: 0.9; margin: 0 0 30px; }
.cta-section .btn-outline { border-color: #fff; color: #fff; }
.cta-section .btn-outline:hover { background: #fff; color: var(--primary); }

/* === Back to Top Button === */
.back-to-top {
  position: fixed; bottom: 30px; right: 30px;
  width: 48px; height: 48px; border-radius: 50%;
  background: var(--primary); color: #fff; border: none;
  font-size: 20px; cursor: pointer;
  box-shadow: 0 4px 15px rgba(var(--primary-rgb), 0.35);
  opacity: 0; visibility: hidden;
  transform: translateY(20px);
  transition: all 0.3s; z-index: 999;
  display: flex; align-items: center; justify-content: center;
}
.back-to-top.visible {
  opacity: 1; visibility: visible; transform: translateY(0);
}
.back-to-top:hover {
  background: var(--primary-dark);
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(var(--primary-rgb), 0.45);
}

/* === Scroll Animation === */
.animate-on-scroll {
  opacity: 0; transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
.animate-on-scroll.animated {
  opacity: 1; transform: translateY(0);
}
.animate-on-scroll.zoom-in {
  transform: scale(0.9);
}
.animate-on-scroll.zoom-in.animated {
  transform: scale(1);
}
.animate-on-scroll.fade-left {
  transform: translateX(-30px);
}
.animate-on-scroll.fade-left.animated,
.animate-on-scroll.fade-right.animated {
  transform: translateX(0);
}
.animate-on-scroll.fade-right {
  transform: translateX(30px);
}

/* === Contact Form Enhancements === */
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: 48px;
}
.contact-info-card {
  background: var(--card-bg); padding: 32px; border-radius: var(--radius);
  box-shadow: var(--shadow-sm); border: 1px solid var(--gray-border);
}
.contact-info-card h3 {
  font-size: 18px; margin: 0 0 20px; color: var(--dark-medium);
}
.contact-info-item {
  display: flex; gap: 12px; margin-bottom: 20px;
  align-items: flex-start;
}
.contact-info-item i {
  width: 40px; height: 40px; border-radius: 50%;
  background: var(--primary-bg); color: var(--primary);
  display: flex; align-items: center; justify-content: center;
  font-size: 16px; flex-shrink: 0;
}

/* === Animation === */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* === Utility === */
.text-center { text-align: center; }
.mt-20 { margin-top: 20px; }
.mt-40 { margin-top: 40px; }
.mb-10 { margin-bottom: 10px; }
.mb-20 { margin-bottom: 20px; }

/* === Form Elements === */
.form-group { margin-bottom: 16px; }
.form-label { display: block; margin-bottom: 6px; font-weight: 600; font-size: 14px; color: var(--dark-medium); }
.form-input,
.form-textarea {
  width: 100%; padding: 12px 14px; border: 1.5px solid var(--gray-border);
  border-radius: var(--radius-sm); font-family: inherit; font-size: 14px;
  color: var(--text); background: var(--card-bg);
  transition: border-color 0.25s, box-shadow 0.25s; box-sizing: border-box;
}
.form-input:focus,
.form-textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-bg); }
.form-textarea { resize: vertical; min-height: 120px; }
.form-row { display: flex; gap: 16px; flex-wrap: wrap; }
.form-row .form-group { flex: 1; min-width: 200px; }
.form-error { background: #fde8e8; color: #c62828; padding: 12px 16px; border-radius: var(--radius-sm); margin-bottom: 16px; font-size: 14px; }
.form-success { background: #e8f5e9; color: #2e7d32; padding: 24px; border-radius: var(--radius-sm); text-align: center; font-size: 16px; font-weight: 600; }

/* === Content Card (detail pages) === */
.content-card {
  background: var(--card-bg); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); padding: 40px; max-width: 960px; margin: 0 auto;
  border: 1px solid var(--border-light);
}
.content-card .content-text { line-height: 1.8; font-size: 15px; color: var(--text); }
.content-card .content-img {
  width: 100%; border-radius: var(--radius-sm); margin-bottom: 28px;
  object-fit: contain; max-height: 450px; cursor: pointer;
}

/* === Back Link === */
.back-link {
  display: inline-flex; align-items: center; gap: 6px;
  color: var(--text-muted); font-weight: 600; font-size: 14px;
  text-decoration: none; transition: color 0.25s;
}
.back-link:hover { color: var(--primary); }

/* === Badges === */
.badge { display: inline-block; padding: 3px 10px; font-size: 11px; font-weight: 600; border-radius: 20px; letter-spacing: 0.3px; }
.badge-photo { background: #3498db; color: #fff; }
.badge-video { background: #e74c3c; color: #fff; }

/* === Meta Text === */
.meta-text { font-size: 13px; color: var(--text-muted); margin: 4px 0; }

/* === Empty State === */
.empty-state {
  background: var(--card-bg); padding: 48px 24px; text-align: center;
  border-radius: var(--radius); box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
}
.empty-state p { font-size: 16px; color: var(--text-muted); margin: 0; }

/* === Social Icons (Footer) === */
.social-icons { display: flex; gap: 10px; margin-top: 20px; }
.social-icon {
  display: inline-flex; align-items: center; justify-content: center;
  width: 36px; height: 36px; border-radius: 50%;
  background: rgba(255,255,255,0.1); color: #fff;
  transition: all 0.3s; text-decoration: none; font-size: 15px;
}
.social-icon:hover { background: var(--primary); color: #fff; }

/* === Section Divider === */
.section-divider { border: 0; border-top: 1px solid var(--gray-border); margin: 28px 0; }

/* === Section Header (inline heading with underline) === */
.section-header {
  font-size: 20px; font-weight: 700; color: var(--dark-medium);
  border-bottom: 2px solid var(--primary); padding-bottom: 8px;
  display: inline-block; margin-bottom: 20px;
}

/* === Hero Simple (compact hero) === */
.hero-simple {
  background: var(--hero-bg); color: var(--hero-text);
  text-align: center; padding: 40px 20px;
}
.hero-simple h1 { margin: 0; font-size: 32px; color: var(--hero-text); }
.hero-simple p { color: var(--hero-text-muted); margin-top: 8px; font-size: 14px; }

/* === Product Detail === */
.product-detail-layout {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start;
}
.product-detail-info { position: sticky; top: 100px; }
.product-detail-info .product-meta {
  display: flex; flex-wrap: wrap; gap: 16px; margin-bottom: 24px;
}
.product-detail-info .product-meta-item {
  padding: 8px 16px; background: var(--gray-bg); border-radius: var(--radius-sm);
  font-size: 13px; color: var(--text-muted); display: flex; align-items: center; gap: 6px;
}
.product-detail-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 28px; }

/* === Sidebar === */
.sidebar { width: 250px; flex-shrink: 0; }
.content-area { flex: 1; min-width: 0; }
.page-layout { display: flex; gap: 30px; }

/* === Pagination (refined) === */
.pagination { display: flex; justify-content: center; align-items: center; gap: 6px; margin-top: 40px; flex-wrap: wrap; }
.pagination a, .pagination span {
  padding: 8px 14px; border-radius: var(--radius-sm); font-size: 14px; font-weight: 500;
  text-decoration: none; transition: all 0.2s;
}
.pagination a { border: 1px solid var(--gray-border); color: var(--dark-medium); }
.pagination a:hover { border-color: var(--primary); color: var(--primary); }
.pagination .current {
  background: var(--primary); color: #fff; font-weight: 600; border: 1px solid var(--primary);
}

/* === Video Cards === */
.video-card .card-body { padding: 16px 18px 18px; }
.video-card .card-title { font-size: 15px; margin-bottom: 8px; }
.video-card .card-title a { color: inherit; text-decoration: none; }
.video-card .card-title a:hover { color: var(--primary); }
.video-thumb-link { display: block; position: relative; overflow: hidden; }
.video-thumb-wrapper { position: relative; }
.video-thumb-wrapper img { display: block; width: 100%; height: auto; aspect-ratio: 16/9; object-fit: cover; transition: transform 0.4s; }
.video-card:hover .video-thumb-wrapper img { transform: scale(1.05); }
.video-play-overlay {
  position: absolute; inset: 0; display: flex; align-items: center; justify-content: center;
  background: rgba(0,0,0,0.25); transition: background 0.3s;
}
.video-card:hover .video-play-overlay { background: rgba(0,0,0,0.4); }
.video-play-overlay i { font-size: 48px; color: rgba(255,255,255,0.9); filter: drop-shadow(0 2px 8px rgba(0,0,0,0.4)); transition: transform 0.3s; }
.video-card:hover .video-play-overlay i { transform: scale(1.1); }

/* === Inquiry Form Contact Info === */
.contact-info-block { line-height: 2; }
.contact-info-block p { margin: 0 0 8px; display: flex; align-items: center; gap: 8px; }
.contact-info-block .icon { color: var(--primary); font-size: 18px; width: 24px; text-align: center; }

/* === Button Reset === */
.btn-reset {
  padding: 11px 28px; background: var(--text-muted); color: #fff;
  border: none; border-radius: var(--radius-sm); font-size: 14px;
  font-weight: 600; cursor: pointer; font-family: inherit;
  transition: background 0.25s;
}
.btn-reset:hover { background: var(--dark-medium); }

/* === RWD Responsive === */
@media (max-width: 768px) {
  .hamburger { display: block; }
  .menu {
    display: none; flex-direction: column;
    position: absolute; top: 100%; left: 0; right: 0;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(12px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.1);
    padding: 12px 0; z-index: 99; gap: 0;
  }
  .menu.active { display: flex; }
  .menu li { margin: 0; }
  .menu a { display: block; padding: 12px 20px; border-radius: 0; font-size: 15px; }
  .menu a.active { border-radius: 0; }
  .hero { padding: 48px 20px; }
  .hero h1 { font-size: 28px; }
  .grid { grid-template-columns: 1fr; gap: 20px; }
  .carousel-track { aspect-ratio: 16 / 9; min-height: 180px; }
  .carousel-caption { font-size: 13px; padding: 6px 16px; }
  .gallery-grid { grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 8px; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .section-title { font-size: 24px; }
  .header .logo span { font-size: 15px; }
  .product-detail-layout { grid-template-columns: 1fr; gap: 24px; }
  .contact-layout { grid-template-columns: 1fr; gap: 24px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; }
  .page-layout { flex-direction: column; }
  .sidebar { width: 100%; }
  .hero-simple h1 { font-size: 24px; }
  .content-card { padding: 24px; }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .grid { grid-template-columns: repeat(2, 1fr); }
  .product-detail-layout { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}